Zig Ziglar, one of the world's most famous salesmen, who inspired millions with his message of positivity and personal achievement, passed away Wednesday at the age of 86 from pneumonia.

He was known around the world as a performance trainer for major corporations, motivational speaker, and author of best-selling books such as See You at the Top and Secrets of Closing the Sale. In his autobiography Zig, published 10 years ago, he wrote, "If my life has had a theme, I suppose it has been a typical American theme in that, for most of it, I have been looking for happiness and success." But his life was remarkable in his dedication to helping others find the same.

What follows are a dozen of Ziglar's most inspirational quotes for achieving personal and professional success.